Channel steel joist reinforced masonry structure lintel and construction method thereof

Abstract

The invention relates to a channel steel joist reinforced masonry structure lintel and a construction method thereof. The channel steel joist reinforced masonry structure lintel comprises a channel steel joist and fastening bolts. The channel steel joists are arranged on the lower portion of a masonry structure lintel crack and symmetrically arranged on the two sides of the lower portion of an original structure lintel. The channel steel joist is fastened and connected with the channel steel joist on the other side of the lintel through a fastening bolt and a nut, and a groove of the channel steel joist is filled and leveled up with plastering mortar; and after the channel steel joists, the fastening bolts and the like are all installed, cement polymerization grouting liquid is poured into the cracks. The channel steel joists are adopted to reinforce lintel cracks of the masonry structure, tensile stress generated by pressure grouting reinforcement can be borne, the ductility of the structure is improved, and the anti-collapse capacity of the structure is enhanced.

Description

Technical Field

[0001] The present invention relates to a channel steel joist for strengthening a masonry structure lintel and a construction method thereof, belonging to the technical field of comprehensive renovation of old residential areas. Background Art

[0002] For existing masonry structure lintels with cracks, the method of pressure grouting reinforcement is usually adopted for strengthening. Pressure grouting is to inject a cement polymer grouting liquid into the cracks, underfilled mortar joints, holes and loose and non-solid masonry structures of the masonry structure by means of compressed air, so as to restore the structural integrity, improve the strength and durability of the masonry structure, and at the same time improve the waterproof and anti-seepage performance of the masonry structure. After being verified by multiple earthquakes, this method is safe and reliable, significantly improves the ductility of the structure, and enhances the anti-collapse ability of the structure. The cement polymer grouting liquid is the most commonly used masonry grouting liquid, which is a certain amount of colloidal suspending agent added to pure cement slurry to improve the bonding ability of the slurry, improve the groutability of the slurry, and enhance the strength of the masonry structure. Before adopting pressure grouting reinforcement for the cracks of the masonry structure lintel, the cracks should be strengthened. Usually, a channel steel joist and fastening bolts are used to reinforce the masonry structure lintel around the cracks to bear the tensile stress generated by pressure grouting reinforcement. The present invention mainly uses a channel steel joist and fastening bolts to reinforce the cracks of the masonry structure lintel, and then conducts pressure grouting reinforcement on the cracks. Summary of the Invention

[0003] The present invention provides a channel steel joist for strengthening a masonry structure lintel and a construction method thereof, mainly for strengthening existing masonry structure lintels with cracks by the method of pressure grouting reinforcement. The present invention adopts the following technical solutions:

[0004] A channel steel joist for strengthening a masonry structure lintel and a construction method thereof, as Figures 1-2 shown, includes a channel steel joist and fastening bolts; the channel steel joist is arranged at the lower part of the crack of the masonry structure lintel, and the channel steel joist is symmetrically arranged on both sides of the lower part of the original structural lintel; both ends of the channel steel joist extend 300 mm along the wall respectively to form a support section of the channel steel joist, and the channel steel joist on the support section of the channel steel joist is all embedded in the wall; the channel steel joist is provided with installation holes for passing through the fastening bolts; the channel steel joist is tightly connected with the channel steel joist on the other side of the lintel through the fastening bolts and nuts, and the groove of the channel steel joist is filled with plastering mortar; after all the channel steel joists, fastening bolts, etc. are installed, a cement polymer grouting liquid is poured into the crack.

[0005] Further, the channel steel joist is a channel steel of 匚10.

[0006] Further, the installation holes on the channel steel joist are φ12, and the distance between the installation holes is not less than 300 mm.

[0007] Furthermore, the fastening bolts are M10 bolts, and the diameter of the holes drilled on the original structural lintel is 12 mm.

[0008] Furthermore, the plastering mortar is a plastering mortar wrapped with steel wire mesh.

[0009] Furthermore, the cement used in the cement polymerization grouting fluid is ordinary Portland cement with a cement strength grade of 42.5, the sand is fine sand with a particle size not greater than 0.5 mm, and the water is drinking water or natural clean water.

[0010] The above-mentioned channel steel joist reinforced masonry structure lintel and its construction method, the specific implementation steps are as follows:

[0011] Step 1: Provide temporary support for the cracked lintel.

[0012] Step 2: Cut grooves on the wall and lintel, and chisel out a 300mm long groove in the supporting section of the channel steel support beam.

[0013] Step 3: Drill fastening bolt holes with a diameter of 12mm on the lintel and channel steel support beam supporting section, and blow away the dust and powder.

[0014] Step 4: Apply cement polymer grouting liquid with a thickness of 3 to 5 mm on the joint surface of the channel steel support beam and the lintel groove, then stick the channel steel support beams on both sides of the lintel and press them tightly.

[0015] Step 5: Use M10 fastening bolts to fasten the channel steel support beams on both sides of the lintel with nuts.

[0016] Step 6: Carry out pressure grouting on the cracks of the wall and lintel, inject cement polymer grouting liquid, let it stand for 1 to 2 days, and then remove the temporary support.

[0017] Step 7: Carry out rust-proof treatment on the exposed channel steel beams and fastening bolts.

[0018] Beneficial effects:

[0019] The use of channel steel beams to reinforce cracks in the lintels of masonry structures can bear the tensile stress generated by pressure grouting reinforcement. This method is simple to construct, safe and reliable, can improve the ductility of the structure, and enhance the structure's ability to resist collapse. It also saves engineering volume, engineering materials, and reduces engineering costs. This method is one of the most cost-effective methods for seismic reinforcement of cracks in existing masonry structure lintels. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 Schematic diagram of the masonry structure lintel reinforced by channel steel joists;

[0021] Figure 2 for Figure 1 AA cross-section diagram.

[0022] In the figure, 1: channel steel joist; 2: fastening bolt; 3: supporting section of channel steel joist; 4: wall; 5: lintel; 6: crack location; 7: nut; 8: plastering mortar. Specific implementation method

[0023] The specific implementation method of the present invention is as follows:

[0024] The channel steel joist for strengthening the lintel of masonry structure and its construction method, as Figures 1-2 shown, is characterized in that it includes a channel steel joist 1 and a fastening bolt 2; the channel steel joist 1 is arranged below the crack of the lintel 5 of the masonry structure, and the channel steel joist 1 is symmetrically arranged on both sides below the original structure lintel 5; both ends of the channel steel joist 1 extend 300 mm along the wall to form a supporting section 3 of the channel steel joist, and the channel steel joist 1 on the supporting section 3 of the channel steel joist is entirely embedded in the wall 4; the channel steel joist 1 is provided with mounting holes for passing through the fastening bolt 2; the channel steel joist 1 is tightly connected to the channel steel joist 1 on the other side of the lintel 5 through the fastening bolt 2 and the nut 7, and the groove of the channel steel joist 1 is filled with plastering mortar 8; after all the channel steel joist 1, fastening bolt 2, etc. are installed, a cement polymer grouting liquid is poured into the crack location 6.

[0025] Further, the channel steel joist 1 is a channel steel of 匚10.

[0026] Further, the mounting holes on the channel steel joist 1 are φ12, and the distance between the mounting holes is not less than 300 mm.

[0027] Further, the fastening bolt 2 is an M10 bolt, and the drilling diameter on the original structure lintel 5 is 12 mm.

[0028] Further, the plastering mortar 8 is plastering mortar with a wire mesh wrapped outside.

[0029] Further, the cement used in the cement polymer grouting liquid is ordinary Portland cement with a strength grade of 42.5, the sand is fine sand with a particle size not greater than 0.5 mm, and the water is drinking water or natural clean water.

[0030] For the above channel steel joist for strengthening the lintel of masonry structure and its construction method, the specific implementation steps are as follows:

[0031] Step 1: Make temporary support for the cracked lintel 5.

[0032] Step 2: Cut grooves on the wall 4 and the lintel 5, and chisel out a 300 - mm - long groove for the supporting section 3 of the channel steel joist.

[0033] Step 3: Drill holes for the fastening bolt 2 on the lintel 5 and the supporting section 3 of the channel steel joist, with a hole diameter of 12 mm, and blow out the dust powder.

[0034] Step 4: Apply cement polymer grouting liquid with a thickness of 3 to 5 mm to the joint surface of the grooved part of the channel steel joist 1 and the lintel 5, and then stick the channel steel joist 1 on both sides of the lintel 5 and press them tightly.

[0035] Step 5: Use M10 fastening bolts 2 to fasten the channel steel support beams 1 on both sides of the lintel 5 through nuts 7.

[0036] Step 6: Perform pressure grouting on the cracks 6 of the wall 4 and the lintel 5, inject cement polymer grouting liquid, let it stand for 1 to 2 days, and then remove the temporary support.

[0037] Step 7: Perform rust-proof treatment on the exposed channel steel joist 1 and fastening bolts 2.

[0038] The above is a typical implementation of the present invention, and the specific implementation of the present invention is not limited thereto.

Claims

1. Channel steel joist reinforced masonry structure lintel and construction method thereof, characterized in that: It comprises a channel steel joist (1) and a fastening bolt (2); the channel steel joist (1) is arranged at the lower part of the crack of the masonry structure lintel (5), and the channel steel joist (1) is symmetrically arranged on both sides of the lower part of the original structure lintel (5); both ends of the channel steel joist (1) are extended 300 mm along the wall to form a channel steel joist support section (3), and the channel steel joist (1) on the channel steel joist support section (3) is completely embedded in the wall (4); the channel steel joist (1) is provided with a mounting hole for passing the fastening bolt (2); the channel steel joist (1) is fastened to the channel steel joist (1) on the other side of the lintel (5) by means of the fastening bolt (2) and the nut (7), and the groove of the channel steel joist (1) is filled with plaster mortar 8; after the channel steel joist (1), the fastening bolt (2), etc. are all installed, cement polymer grouting liquid is poured into the crack (6).

2. The channel steel joist reinforced masonry structure lintel and the construction method thereof according to claim 1 are characterized in that: The channel steel support beam (1) is a channel steel of size 10.

3. The channel steel joist reinforced masonry structure lintel and the construction method thereof according to claim 1 are characterized in that: The mounting holes on the channel steel joist (1) are φ12, and the spacing between the mounting holes is not less than 300 mm.

4. The channel steel joist reinforced masonry structure lintel and the construction method thereof according to claim 1, characterized in that: The fastening bolt (2) is an M10 bolt, and the diameter of the hole drilled on the original structural lintel (5) is 12 mm.

5. The channel steel joist reinforced masonry structure lintel and the construction method thereof according to claim 1, characterized in that: The plastering mortar 8 is a plastering mortar covered with steel wire mesh.

6. The channel steel joist reinforced masonry structure lintel and the construction method thereof according to claim 1, characterized in that: The cement polymerized grouting liquid uses ordinary Portland cement with a cement strength grade of 42.5, the sand is fine sand with a particle size not greater than 0.5 mm, and the water is drinking water or natural clean water.

7. The channel steel joist reinforced masonry structure lintel and the construction method thereof according to any one of claims 1 to 6, characterized in that: Use the following steps: Step 1: Temporarily support the cracked lintel (5). Step 2: Cut grooves on the wall (4) and the lintel (5), and chisel out a 300 mm long groove of the channel steel joist support section (3). Step 3: Drill holes for fastening bolts (2) on the lintel (5) and the channel steel joist support section (3), with a hole diameter of 12 mm, and blow away the dust. Step 4: Apply cement polymer grouting liquid with a thickness of 3 to 5 mm to the joint surface of the grooved part of the channel steel joist (1) and the lintel (5), and then stick the channel steel joists (1) on both sides of the lintel (5) and press them tightly. Step 5: Use M10 fastening bolts (2) to fasten the channel steel support beams (1) on both sides of the lintel (5) through nuts (7). Step 6: Pressure grouting is performed on the cracks (6) of the wall (4) and the lintel (5), and cement polymer grouting liquid is poured in. After standing for 1 to 2 days, the temporary support is removed. Step 7: Perform rust-proof treatment on the exposed channel steel joist (1) and fastening bolts (2).

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